rock trout
noun
1 NZ any of several New Zealand freshwater fishes of the genus Galaxias (family Galaxiidae), especially the giant kokopu, G. argenteus, and the inanga, G. maculatus (now historical ).
2 US any of various greenlings (family Hexagrammidae) of the east Pacific, especially of the genus Hexagrammos (now rare ).
Origin
Mid 19th century; earliest use found in John Edward Gray (1800–1875), zoologist and museum curator.